1. Field of the Invention
The invention pertains to a hydrodynamic clutch device of the type including a clutch housing which is rotatable about an axis of rotation and has a drive-side housing wall, a hydrodynamic circuit including a pump wheel and a turbine wheel in the clutch housing, and a bridging clutch having a piston capable of shifting axially relative to the drive-side housing wall, the piston separating a pressure space adjacent to the drive-side housing wall from a supply space.
2. Description of the Related Art
A hydrodynamic clutch device designed as a hydrodynamic torque converter is known from U.S. Pat. No. 5,964,329. A pump wheel cooperates with a turbine wheel and a stator to form a hydrodynamic circuit in a clutch housing; this circuit cooperates with a bridging clutch. The bridging clutch has a piston, which can be connected to a drive-side housing wall of the clutch housing and shifted in the axial direction. This piston is supported by way of a seal on a housing hub, which is mounted on the drive-side housing wall. This housing hub, which acts as a component of the clutch housing, serves as an axial stop for another hub, which holds the turbine wheel and possibly also a component of a torsional vibration damper. For this purpose, the side of this hub facing the housing hub is provided with a stop element, while the opposite axial side is supported by an axial bearing against the stator, which is provided as a component of the hydrodynamic circuit.
First flow channels are provided in the housing hub, and second flow channels are provided in the stop element assigned to the hub. The flow channels of the housing hub are in flow connection with first flow passages in the hub, whereas the flow channels in the stop element are in flow connection with second flow passages in the hub, where the first flow passages are axially offset from the second flow passages. By way of the first flow passages, at least one first takeoff-side flow route is connected to a pressure space, which is bounded at least essentially by the drive-side housing wall of the clutch housing and the piston, and by way of the second flow passages at least one second takeoff-side flow route is connected to a supply space, which is adjacent to the side of the piston facing away from the pressure space.
The disadvantage of the known hydrodynamic clutch device is the considerable expense which is associated with the housing hub mounted on the drive-side housing wall, because this housing hub not only must be dimensioned in the axial direction in such a way that it positions the hub, which holds the turbine wheel and/or a component of the torsional vibration damper axially with respect to the stator, but also must be dimensioned radially in such a way that it centers the hub and also the piston of the bridging clutch. It must also be ensured, furthermore, that the flow channels of the housing hub are at least essentially aligned with the flow passages of the hub. The hub which holds the turbine wheel and/or a component of the torsional vibration damper is also difficult and expensive to manufacture, because it has a complicated geometry and also because it must contain the first and the second flow passages.